technoguy

Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength. The elementary particle that defines light is the photon. The three basic dimensions of light (i.e., all electromagnetic radiation) are:

Desiree

The spetrum acount for the compination of these wave lengths that creates what we call light, is that right?

technt77

That makes sense to me. I guess I never think about the actual scientific description of light. I just think of it as the absence of darkness.

yellowbird

How the light enters the eye so that we can actually see the light, is also interesting. First, light enters through the cornea and then through the lens of the eye. Vitreous humor fills the inside of the eye in which light also passes to get to the back of the eye where the retina is. The retina contains cones and rods, which actually light us see the light. Different types of cones allow us to see colors. Rods light us see dim light or our night vision. The optic nerve transfers the light images to our brain, which in turn tell us exactly what it is we are looking at, or what color, etc.

Trinity

Amazing---the human body----a self healing programable computer.

Trinity

Missing cones or Rods??? What is it---a color blind person sees tones of grey and opposite colors??Ie red as green??

rjpeters

It is a result of a lack of one or more of the types of color receptors. Most are red or green or both. These are also mostly men. It is caused by a lack of red receptors. Yellow/blue is the second most common form but it is extremely rare. It is possible to have the color receptors missing entirely and to see only in black and white. It is a genetic condition usually but it is possible to acquire it as well.

Desiree

I appreciate the info.

vipl

Being color-blind can make it tricky to match your shirt and pants, but it's not a serious problem. People who are color-blind can do normal stuff, even drive. Most color-blind people can't tell the difference between red or green, but they can learn to respond to the way the traffic signal lights up. The red light is generally on top and green is on the bottom.